[April 16, 2014]WASHINGTON (Reuters) — Lawmakers
probing how General Motors used faulty ignition switches in many
vehicles are turning their scrutiny to the supplier of the part, Delphi
Automotive.

A group of senators on Tuesday wrote to Delphi Chief Executive
Officer Rodney O'Neal, asking for information about whether the
parts supplier pushed back against GM after the automaker apparently
did not accept a proposed fix to the switches.

"It is our understanding that a fix was proposed by Delphi regarding
the ignition switch in 2005 but GM did not adopt the change," the
letter said. "As we continue evaluating the GM recall it is
critically important that we understand the decisions made by Delphi
and the company's interaction with GM."

Senate Commerce Chairman Jay Rockefeller, a Democrat, signed the
letter along with three fellow senators — John Thune, the top
Republican on the panel, Democrat Claire McCaskill and Republican
Dean Heller.

A spokeswoman for Delphi did not immediately respond to a request
for comment.

Congressional investigators have so far mostly focused their
attention on GM and the National Highway Traffic Safety
Administration, which have both come under scrutiny for not acting
on years of warning signs about the deadly defect.

GM has recalled 2.6 million vehicles, including Chevrolet Cobalts
and other models with ignition switches prone to being bumped or
jostled into accessory mode while cars were moving, which could shut
off engines and disable power steering, power brakes and airbags.

The faulty part has been linked to at least 13 deaths. GM has hired
former federal prosecutor Anton Valukas to conduct an internal
investigation into the faulty switches and subsequent recalls.

Delphi officials have told investigators from the House of
Representatives that GM approved the ignition switches, even though
the parts did not appear to meet GM's own specifications.

Delphi has also been drawn into a mounting wave of litigation for
its role in producing the faulty switch that prompted the recalls.

The senators on Tuesday asked Delphi whether the parts supplier
originated the discussion to fix the part, or if GM did. They also
asked for the reasons why a design change was rejected in 2005, if
Delphi protested the decision, and if Delphi communicated with NHTSA
about the ignition switch.

The senators asked for answers by April 28.

It is unclear if Delphi executives will be called to testify. After
holding hearings earlier this month with GM CEO Mary Barra and the
NHTSA chief David Friedman, lawmakers expect to zero in on GM
engineers critical to the development and oversight of the faulty
switches.